Fix for empty saveLayer() with a filter which affects transparent black.

src/core/SkPictureRecord.cpp

 /*
  * Copyright 2011 Google Inc.
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 
 #include "SkPictureRecord.h"
 #include "SkTSearch.h"
 #include "SkPixelRef.h"
@@ skipping 275 matching lines @@
  */
 static bool match(SkWriter32* writer, uint32_t offset,
                   int* pattern, CommandInfo* result, int numCommands) {
     SkASSERT(offset < writer->bytesWritten());
 
     uint32_t curOffset = offset;
     uint32_t curSize = 0;
     int numMatched;
     for (numMatched = 0; numMatched < numCommands && curOffset < writer->bytesWritten(); ++numMatched) {
         DrawType op = peek_op_and_size(writer, curOffset, &curSize);
-        while (NOOP == op && curOffset < writer->bytesWritten()) {
+        while (NOOP == op) {
             curOffset += curSize;
+            if (curOffset >= writer->bytesWritten()) {
+                return false;
+            }
             op = peek_op_and_size(writer, curOffset, &curSize);
         }
 
-        if (curOffset >= writer->bytesWritten()) {
-            return false; // ran out of byte stream
-        }
-
         if (kDRAW_BITMAP_FLAVOR == pattern[numMatched]) {
             if (DRAW_BITMAP != op && DRAW_BITMAP_MATRIX != op &&
                 DRAW_BITMAP_NINE != op && DRAW_BITMAP_RECT_TO_RECT != op) {
                 return false;
             }
         } else if (op != pattern[numMatched]) {
             return false;
         }
 
         result[numMatched].fActualOp = op;
@@ skipping 1327 matching lines @@
 }
 
 void SkPictureRecord::addPoints(const SkPoint pts[], int count) {
     fWriter.writeMul4(pts, count * sizeof(SkPoint));
 #ifdef SK_DEBUG_SIZE
     fPointBytes += count * sizeof(SkPoint);
     fPointWrites++;
 #endif
 }
 
+void SkPictureRecord::addNoOp() {
+    size_t size = kUInt32Size; // op
+    this->addDraw(NOOP, &size);
+}
+
 void SkPictureRecord::addRect(const SkRect& rect) {
 #ifdef SK_DEBUG_SIZE
     size_t start = fWriter.bytesWritten();
 #endif
     fWriter.writeRect(rect);
 #ifdef SK_DEBUG_SIZE
     fRectBytes += fWriter.bytesWritten() - start;
     fRectWrites++;
 #endif
 }
@@ skipping 160 matching lines @@
 void SkPictureRecord::validateRegions() const {
     int count = fRegions.count();
     SkASSERT((unsigned) count < 0x1000);
     for (int index = 0; index < count; index++) {
         const SkFlatData* region = fRegions[index];
         SkASSERT(region);
 //        region->validate();
     }
 }
 #endif